I was just about to post that link. While my knowledge of different teaching techniques is limited, from what I can tell they are mostly opposed to more freeform education which is likely to deviate from the set education standards and curriculum. Not totally surprising for a conservative perspective.. but it's less likely to do with challenging religion than most hackernewsers would think. They probably see these alternative forms as hippy free-thinking ways that will produce individuals that want to live within a different system, mostly by deviating from traditional workforce paths and not respecting existing authority and hierarchy.